1) Field
This disclosure generally relates to a method for manufacturing a solar cell.
2) Description of the Related Art
A solar cell is a photoelectric conversion device that transforms photonic energy, e.g., solar energy, into electrical energy, and has been recognized as a renewable and pollution-free next generation energy source.
A solar cell typically includes p-type and n-type semiconductors and produces electrical energy by transferring electrons and holes to the n-type and p-type semiconductors, respectively, and then collecting electrons and holes in electrodes when an electron-hole pair (“EHP”) is produced by photonic energy absorbed in a photoactive layer inside the semiconductors.
Further, it is desirable for a solar cell to be as efficient as possible for producing electrical energy from photonic energy, e.g., solar energy. In order to increase the efficiency of a solar cell, it is important to increase a light absorption rate thereof. While short-wavelength light is easily absorbed by a semiconductor substrate (e.g., silicon crystal), long-wavelength light is rarely absorbed but is instead transmitted through the crystal in the semiconductor substrate, e.g., silicon crystal. Furthermore, long-wavelength light is more easily transmitted if the substrate of the solar cell is thinner, that is to say that an increase of transmission of long-wavelength light through the semiconductor substrate is inversely proportional to an increase in the thickness thereof.